Apparatus for flattening bulbs of thermometer tubes



Feb24, 1931*.

APPARATUS FOR FLATMLNING BULEM@ GF THERMOMETER TUM@ INVENTR ATTORNEYS Patented heb.. 2li, 193i s'rA LEE F. CHANEY, OF SPRINGFIELB, DHIO PPARATUS :F011V FLATTENING BULBS 0F THERMUMETER TUBES Application led January 8, 1929. Serial No. 331,130.

This invention relates to apparatus for flat? tening 'the bulbs of thermometers.

An object of the invention is to provide a simple, efficient, and inexpensive device t'or 5 producing flat-bulb thermometers.

A fur-t er and more specific object of the invention is to provide an arrangement in which the hammer for flattening the bulbs is operated pneumatically and a single control valve is employed to simultaneously supply air to the hammer cylinder and to the bulbs while being flattened.

Other objects and advantages will appear trom the following description and claims.

.ln the accon'lpanying drawing:

Fig. i. is a ltop plan view of the improved apparatus.

Fig. 2 is a side elevation of that portion of the apparatus in Which the bulb is flattened.

Fig. 3 is a partial front elevation of the flattening apparatus.

Fig. t is an enlarged fragmentary elevation of portions shown in Fig. 2, but with some of the parts in a ditlerent Working poi sition.

Fig. 5 is an enlarged vertical section on the line 5 5 oi Fig. 1.

Fig. 6 is an enlarged perspective view of a typical thermometer tube, at one stage of 'v the manufacturing process.

Fig. 7 is an end elevation ot a thermometer tube in a` succeeding stage of the process of manufacture.

Fig. 8 is a partial side elevation of the flattening apparatus, looking at the side opposite that shown in Fig. 2.

Referringto the drawing, 1 represents a flat metallic angularly shaped lever pivotally connected to a'standard 2, which in turn is adjustably secured to a supporting base 3, which in turn is mounted upon a suitable table not shown). At 4 the base is provided with an inclined anvil face, which cooperates with the end of' the arm 1 of the lever 1. and

both the tace t and the end of the* arm are U mica secured in place on the :tace 4 by the clamping members 9 und 10, the purpose of the heat-insulation appearing at a later point in the description.

The arm 1 ot' the lever is in effect a hainmer, and to actuate the hammer, I provide a fluid-pressure cylinder 11 formed by a vertical bore in the rear portion of the base 1, and in'which is fitted a piston 12 having a piston rod 13 which passes through the upper end of the cylinder. The lower end of the cylinder is plugged as at 14;, and air under slight pressure is conveyed to the cylinder by means of the hose 15, and through the connector 16 to the ports 17, and on admission of compressed air to the lower side of the piston 12, it rises and strikes the arm 1H of the lever which is directly in the path of the piston rod, causing the end ot the hammer arm 1 to descend towards the anvil face. The upward travel of the piston is lirnited by a, stop 18 adjustably secured to a standard 19 inserted in the body7 3, and by suitable regulation of the stop 18, and also by suitable adjustment of the standard 2, the :tace of the hammer is stopped any desired distance from the face of the anvil, the inclinations of the arm and anvil being such that they Will at this point be parallel to each other. The standard 2 is adjustably mounted on the base 1 by a cap screw 20 which passes through a slotted opening 20 in the standard. A spring 21 is employed to etifect a ready return ot the piston 12 to the lower position, while a light spring 22 serves to retain the hammer in its raised position, as shown in Fig. 2.

lt will be understood that the lulbs are blown at one end of the glass thermometer tubes, T representing the tube with its bore 7), the crosssection shown inFigs. 6 and 7 bcing that of a typical prevailing type of tube, the advantages being that the edge E acts as a magnifier to facilitate observation. As the scale of graduations S should be placed behind the tube opposite the edge E, it is obvious that the round bulb, such as is shown in Fig. 6 will not stand parallel to the scale through its entire length unless a depression is made to receive it. Accordingly the fiat bulb came into use, and as shown in Fig. 7, W

the short axis of the bulb B is in alignment with the edge E and the bore b.

j The tube to be blown is inserted in the end of a hose 23, the other end of which is connected to a T 24, one of its branches connected to the hose and the other to a valve mechanism V, the )arts and functions of which will be explained.

The valve body is represented by 25, and is provided at its lower end with an interiorly threaded extension 26 in which is screwed a pipe 27 connected to any suitable source of compressed air supply. A ball 28 is held against a seat in a bore 28 by a spring 29, which is retained by a cross pin 30, and limits or shuts oft entirely the flow of air through the-remainder of the valve. An oritice 31 is provided and communicating with it is another orifice 32 leading toa connector 33 and thence to the hose 23.

An upward extension 34C has inserted therein a length of pipe 35, in the bore of lwhich is a rod 36, having a reduced-diameter extension 37 resting on the ball 28. Pressure on the rod 36 forces the ball from its seat and allows air to flow into the orifice 31., the airstream dividing, a portion flowing into the hose 23 and 15 and the remainder flowing upwardly through the pipe 35. It should be seen from this thatthe quantity flowing into the hose 25 may be varied by partially closing the end of the pipe 35 while at the same time the ball 28 is being held from its seat, which is in Jfact the method of operation; that is, the operator places the end of a linger over the open end of the pipe 35, and by slight rocking downward pressure, the finger' is made to cont-act the end of the rod 36 and at the same time to constrict the flow of air from the end of the pipe 35.

After insertingthe tube T in the hose 523 and holding the opposite end in a flame (not shown) fusion takes place, when lthe operator, by manipulating the rod 36 and partially constricting the flow from pipe 35, as previously explained, causes the heated end of the tube to expand into the round bulb shape seen in Fi 6. A gage 39 having openings 40 of di erent sizes is rovided, it being adjusted to present to the ront the size intended, and by continuing the blowing operation with the expanding bulb adjacent the desired opening the operator may observe and limit further expansion by removing the finger closure to a greater degree.

The operator then places the fused end of the tube on the anvil and in order to correctly position the same thereon there is provided a rest formed by a recess 41 in the forward edge of a plate 41, which, is secured to the side of the base by a strap 41a, and also a gage 42 consisting of a plate preferably of mica which is secured to the base adjacent the anvil; the under side of the mica `plate acting as a gage arranged perpendicular `to the face messer of the anvil and substantially in line with the recess 1&1. ll/hen the tube is inserted it is turned so that the edge E faces the operator, with the convex portion` thereof rest-ing in the. rounded recess. ln order that the tube may be accurately positioned, there is also attached to the hammer arm another gage member 43, which is formed of a flat strip ot' spring steel and has a downwardly projecting extension 4st in which is a vi-notch 45 which engages the V-shaped portion of the tube so as to rotate the tube if necessary to correctly position it. This strip also has a .slotted opening 43 to better observe the positioning of the bulb of the tube on the anvil in a crosswise direction. The extension Llei of the hammer gage is of such length and arrangement as to contact the tube l before the hammer strikes the bulb and the pressure ot this gage upon the tube is suflicient to insure the tube being held in proper position so that the bulb as finallyformed will be in proper relaticn to the edge E of the tube. To operate the hammer after the tube has been inserted, the

operator merely closes the end of the tube il@ with his linger so as lo create a pressure et air surtir-,lent to operate the piston in the cylinder; it being understood that in the of blowing the bulb the operator does not completely close the upper end of the tube thus permitting some of the air to I, therethrou h and give a sueien-t pressure only for t e purpose of blowing the bulb. `When the tube however is closed te clerate the hammer, the bulb will be subjected to a moment-ary increase of pressure.v which is advisable to prevent collapsing ot the bulb by the impact of the hammer and to assist in preserving the symmetrical appearance: this increased pressure being resisted by the bulb due to the fact that the bulb has contr-d to some degree after it is removed from the fusing flame. By the use or the mica strips on the hammer and anvil the cracking of t'nc tubes from a too sudden change in temperature is obviated, since the mica, being a non conductor of heat, prevents sudden dissipation of the heat of the bulb as would be the case if the bulb was subjected to the. action of metallic surfaces during the operation et l flattening. The non-heat conducting char-- acter of these mica faces also prevents dish ing of the sides of the bulb which would likely occur with metallic surfaces due to the fact that the metallic Surfaces would first strike and chill diametrically opposite points et the bulb and that these chilled portions ot the bulb would have a tendency to press in or dish during the flattening operation.

Having thus described my invention, l

claim:

1. 4In an apparatus of the character de scribed, a fixed anvil, a movable hammer cooperating with said anvil, means for operating said hammer, and faces of non 'heat-con m l ff) ducting material for said hammer and anvil.

2. In an apparatus of the character described, an anvil, a movable hammer cooperating with said anvil, means for operating said hammer, and cooperating mica faces secured to the anvil and hammer.

3. In an apparatus of the character described, a fixed anvil, a movable hammer cooperating with sad anvil, means for o rating sald hammer, a fixed gage for t ermometer tubes adjacent said anvil, and a movable gage for said tube controlled by said hammer, the engaging ortion of said mga le gage conforming to tlie shape of said tu 4. In an apparatus of the character described, a fixed anvil, a movable hammer cooperating with said anvil, means for operating said hammer, a fixed gage* for thermometer tubes adjacent sai anvil, and a movable gage for said tube controlled by said hammer, said movable gage having a VP shapedportion to cooperate with a V-shaped portion of said tube.

5. In an apparatus of the character described, a base having an inclined anvil face, a movable hammer cooperating with said anvil, together with means for operating said hammer, a gage member fixed to said base having an edge extended at right angles to the face of said anvil, a rest for thermometer tubes also carried by said base substantially in line with said fixed gage, and a second gage carried by said hammer adapted to engage a thermometer tube positioned on said anvil, fixed gage and rest, said movable gage having a part conforming to the shape of the tu e.

6. In an apparatus of the character described, a xed anvil, a movable hammer cooperating With said anvil, means for operating said hammer, a fixed gage for thermometer tubes adjacent said anvil, and a yieldable gage carried by said hammer having a portion conforming to the shape of said tube.

7. In an apparatus of the character described, an anvil, a movable hammer cooperating with said anvil, a fluid pressure connection for thermometer tubes, a fluid pressure cylinder for operating said hammer having a fluid pressure connection, and a common controlling device for the fluid pressure source for both of said connections.

8. In an apparatus of the character described, an anvil, a movable hammer cooperatin(r with said anvil, a luid pressure cylinder tfor operating said hammer, a connection form a fluid pressure source to said cylinder, a iluid pressure connection for thermometer tubes, a valve chamber, a valve therein for controlling both of said connections, an operating device for said valve under the control of the operator, and an air relief outlet communicating with said valve chamber also under the control of the operator.

, close 9. In an apparatus of the character described, an anvil, a movable hammer coo ratin with said anvil a fluid pressure cy i der or operating said hammer, a connection from a fluid pressure source to said cylinder, a fluid pressure connection for thermometer tubes, a valve chamber between the source of suppl and `said connections, a normally valve therein for controlling both of said connections, an open ended tube communicating with said valve chamber, and a rod in said tube operatively associated with said valve.

` In testimony whereof, I have hereunto set my hand this 5th day of Januar 1929.

" LEE F. HANEY. 

